1. Field
The present invention relates to a method and system to recover waste heat to preheat feed water for a reverse osmosis unit.
2. Description of the Related Art
A conventional reverse osmosis unit receives feed water and filters the feed water to generate permeate and concentrate. The reverse osmosis unit uses filters in filter banks to filter the feed water. The performance of the filters, however, is impacted by the temperature of the feed water. Feed water with too low of a temperature can decrease yield of the feed water, or the amount of permeate generated compared to the amount of concentrate generated. Conversely, feed water with too high of a temperature can damage the filters in the filter banks. However, adjusting the temperature of the feed water can be costly and require a large expenditure of energy.
Thus, there is a need for a method and system to recover waste heat to preheat feed water for a reverse osmosis unit.